We discuss methods based on principal component analysis to constrain the dark energy equation of state using a combination of Type la supernovae at low redshift and spectroscopic measurements of ...varying fundamental couplings at higher redshifts. We discuss the performance of this method when future better-quality data sets are available, focusing on two forthcoming European southern observatory (ESO) spectrographs-Echelle spectrograph for rocky exoplanet and stable spectroscopic observations (ESPRESSO) for the very large telescope (VLT) and Cosmic dynamics explorer (CODEX) for the European extremely large telescope (E-ELT)-which include these measurements as a key part of their science cases. These can realize the prospect of a detailed characterization of dark energy properties almost all the way up to redshift 4.
Abstract
Background
Brugada Syndrome (BrS) is an inherited disorder associated with an increased risk of sudden cardiac death (SCD) and is diagnosed by the presence of a Brugada type I ECG pattern, ...either spontaneous or drug-induced. A spontaneous ECG pattern is one of the two main risk factors for SCD, along with syncope. However, there is still no clear evidence on how and how often to screen patients with drug-induced BrS to detect a spontaneous ECG pattern, therefore allowing to reassess their arrhythmic risk.
Purpose
To determine how many subjects develop a spontaneous ECG pattern among a pool of patients with low risk BrS (drug-induced pattern without history of syncope at the time of diagnosis) observed through systematic ECG Holter monitoring.
Methods
We retrospectively collected data for all patients with low risk BrS treated at our center for at least 12 months between 2016 and 2021. Each patient was tested yearly with at least one 12-lead 24-hour ECG Holter monitoring with high precordial leads (V1-V2, V3-V4, V5-V6 respectively in 2nd, 3rd and 4th intercostal space parasternal left and right). In case of spontaneous pattern detection at two recordings, patients underwent electrophysiological study (EPS) and in case of inducible ventricular arrhythmias, implantable cardiac defibrillator (ICD) placement.
Results
We included 63 patients with low risk BrS. During a median follow-up of 48 months: 1 patient died for SCD (1.6%), 1 experienced syncope (1.6%) and 19 exhibited a spontaneous ECG pattern (30.2%). Of these 19 patients: 18 were males and 5 had a mutation of SCN5A; the average age at the time of spontaneous pattern detection was 48.1±11.5 years. The average number of ECG holters/per patient/per year was 1.1±0.6, the average number of ECG Holters until the detection of a spontaneous pattern was 3.3±1.8, whilst the average number of months in between the diagnosis and the detection of a spontaneous pattern was 43.2±41.1.
After the observation of a spontaneous pattern: 6 patients were excluded from further investigation (as they had already undergone EPS or refused), 1 was directly treated with ICD and 12 underwent EPS, 4 of whom consequently underwent ICD placement. Among these 5 patients who underwent ICD placement – 7.9% of the original 63 patients – we observed 1 appropriate ICD intervention (antitachycardia pacing), 1 inappropriate ICD shock and 1 ICD related complication.
Conclusions
In our population of patients with low risk BrS the detection of a spontaneous ECG pattern is the most common determinant of risk reclassification. Systematic ECG Holter monitoring disclosed the presence of a spontaneous ECG pattern in a relevant number of subjects, allowing to reassess their arrhythmic risk and indication for ICD placement. Our study stresses the importance of periodic evaluation of low risk BrS patients with ECG Holter monitoring and the need for further investigation to define the optimal monitoring strategy.
Funding Acknowledgement
Type of funding sources: None.
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Ventricular preexcitation (VPE) due to atrio-ventricular accessory pathways (AP) has been associated to a higher incidence ...of sudden cardiac death (1,2). The incidence of major arrhythmic events (MAE) may be higher in children (1,3), but most of the past studies recruited a high proportion of patients with congenital heart disease (CHD), treated with outdated pharmacological therapy (1). Transcatheter ablation (TCA) of the AP is a safe and effective therapy and it is nowadays the standard of care (1,2). However, it may be less effective and more dangerous in smaller and younger children (1,3). It is described that patients may spontaneously lose VPE during childhood (1), but the natural history of VPE is not well understood yet.
Purpose
To study the natural history of VPE. We focused especially on the likelihood of spontaneous resolution of VPE during growth, the possible associated factors, and the incidence of MAE during a long follow up in a contemporary paediatric cohort.
Methods
We retrospectively recruited patients diagnosed with VPE at age 0 to 12, referred from 1993 to 2021 to two tertiary care hospitals. Significant CHD and double AP were excluded. The primary outcome was the spontaneous resolution of VPE, defined by the loss of short PR and delta wave seen in at least two consecutive ECG and/or on 24-hour Holter monitoring. The follow up stopped when the patients reached 16 years of age, met the primary outcome or effective TCA was performed. Given the time-to-event dependency of the condition, the survival analysis of VPE considered the left truncation resulted from the recruitment of patients after the first days of life.
Results
We recruited 153 patients with a median age of diagnosis of 4.9 (0.2 – 8.4). The median follow-up time was 4.9 (1.6 – 8) years. During follow-up, 42 (28%) patients spontaneously loss VPE. The left truncated Kaplan-Meier survival curve of VPE is shown in Picture 1. It estimates that VPE would persist in 53% (40.1-70.2) and 33.8% (23.7-48.4) of patients at the age of 1 and 16, respectively. Symptoms and intermittent preexcitation were the only variables significantly associated with lower (OR 0.2) and higher probability (OR 3.45) of SR of VPE. The vast majority of patients with symptoms was treated with drug therapy before the age of 8, and TCA was safely delayed thereafter. None of the patients experienced a MAE during follow up.
Conclusion
According to our data, a large proportion of paediatric patients are likely to spontaneously lose VPE within the first year of life, and a spontaneous resolution may occur later during childhood in a non-negligible number of cases. The absence of symptoms and/or intermittent preexcitation are significant predictors of loss of VPE. The results of our study are of the utmost clinical relevance, since they support a wait-and-see strategy, especially in very young children with VPE.
VPE survival curve.
Cox regression analysis results.
The multigap resistive plate chamber as a time-of-flight detector Akindinov, A; Anselmo, F; Basile, M ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2000, Letnik:
456, Številka:
1
Journal Article
Recenzirano
The goal of this R&D has been to reach the time resolution needed for Time-of-Flight detectors using the Multigap Resistive Plate Chamber (MRPC). We present here a MRPC with a time resolution of 70 ...ps. This prototype has been studied within the R&D program for the very large area TOF array of the ALICE experiment at the CERN LHC.
We analyze the solutions, on single network instances, of a recently introduced class of constraint-satisfaction problems (CSPs), describing feasible steady states of chemical reaction networks. ...First, we show that the CSPs generalize the scheme known as network expansion, which is recovered in a specific limit. Next, a full statistical mechanics characterization (including the phase diagram and a discussion of the physical origin of the phase transitions) for network expansion is obtained. Finally, we provide a message-passing algorithm to solve the original CSPs in the most general form.
The author proposes that developmental research into the main experiential components of internal working models and process research into central patterns of interaction between analyst and patient ...may share similar theoretical assumptions. A developmental hypothesis bridging these two areas of research is proposed, in which repeated success or difficulty in mutual regulation during infancy result in an emotionally charged set of 'prototypical expectations' that continually influence the sense of personal safety. The author argues that prototypical expectations interfere in the psychoanalytic process because they allow the defensive warding off of negative expectations and so parallel explorations of new relational solutions. An analysand's narratives can be considered to express the conflict between negative transference (generally expressed in relation to extra-transference interactions) and defensive positive transference (more likely to be explicitly connected with the therapeutic situation). During the analytic process, ambivalent transference should appear in both 'worst' and 'best' types of narrative as an indication of warded-off negative transference working through. In this paper an application of the negative prototypical expectations processing hypothesis is presented through a formal discussion of the relational structure of the narratives of a 17-year-old boy's first four analytic sessions. The author demonstrates that this hypothesis makes it possible to predict the transference and the countertransference topics with which the patient and the analyst will have to cope during the treatment.
The authors address the issue of inferring unconscious internal working models of interaction through language. After reviewing Main's seminal work of linguistic assessment through the 'adult ...attachment interview', they stress the idea of adults' internal working models (IWMs) as information-processing devices, which give moment-to-moment sensory orientation in the face of any past or present, animate or inanimate object. They propose that a selective perception of the objects could match expected with actual influence of objects on the subject's self, through very simple 'parallel-processed' categories of internal objects. They further hypothesise that the isomorphism between internal working models of interaction and grammatical connections between subjects and objects within a clause could be a key to tracking positive and negative images of self and other during discourse. An experiment is reported applying the authors' 'scale of subject/object affective connection' to the narratives of sixty-two subjects asked to write about the 'worst' and 'best' episodes of their lives. Participants had previously been classified using Hazan & Shaver's self-reported 'attachment types' (avoidant, anxious and secure) categorising individuals' general expectations in relation to others. The findings were that the subject/object distribution of positive and negative experience, through verbs defined for this purpose as either performative or state verbs, did significantly differ between groups. In addition, different groups tended, during the best episodes, significantly to invert the trend of positive/negative subject/object distribution shown during the worst episode. Results are discussed in terms of a psychoanalytic theory of improvement through co-operative elaboration of negative relational issues.
We discuss methods based on Principal Component Analysis to constrain the dark energy equation of state using a combination of Type Ia supernovae at low redshift and spectroscopic measurements of ...varying fundamental couplings at higher redshifts. We discuss the performance of this method when future better-quality datasets are available, focusing on two forthcoming ESO spectrographs - ESPRESSO for the VLT and CODEX for the E-ELT - which include these measurements as a key part of their science cases. These can realize the prospect of a detailed characterization of dark energy properties almost all the way up to redshift 4.
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